Conventionally, an exhaust gas processing device for a diesel engine includes a DPF, a PM deposition amount detecting unit for PM deposited in the DPF, a forcible regenerating unit, a forcible regeneration control unit, and a forcible regeneration notifying unit (for instance, see FIGS. 1 and 2 in Patent Document 1).
In this conventional technique, when the DPF captures the PM in exhaust gas to cause a first state in which a PM deposition amount detection value reaches a first set value, forcible regeneration at driving which operates the forcible regenerating unit at the time of driving a vehicle is automatically started to combust and remove the PM, and when the PM cannot be combusted and removed in the forcible regeneration at driving to cause a second state in which the PM deposition amount detection value is further increased to reach a second set value which is higher than the first set value, the forcible regeneration notifying unit is operated to notify that it is necessary to perform forcible regeneration at stopping which operates the forcible regenerating unit at stopping.
However, in this conventional technique, after the PM deposition amount detection value reaches the first set value to start the forcible regeneration at driving, unless the PM deposition amount detection value reaches the second set value which is higher than the first set value, the necessity of the forcible regeneration at stopping cannot be notified. So it is a problem.